(a) Field of the Invention
The present invention relates to a control apparatus of a hybrid electric vehicle, and a control method of the hybrid electric vehicle, which can prevent the hybrid electric vehicle from starting irrespective of an intention of a driver.
(b) Description of the Related Art
A hybrid vehicle is a vehicle that uses at least two power sources. Generally, a hybrid vehicle is operated by an engine and a motor. Various types of hybrid electric vehicles can be manufactured by using an engine and a motor.
Generally, a TMED (transmission mounted electric device) type of power train in which a motor, a transmission, and a driving shaft are serially connected is used in a hybrid electric vehicle. A clutch is provided between the engine and the motor, and the hybrid electric vehicle can be driven in an EV (electric vehicle) mode or an HEV (hybrid electric vehicle) mode according to engagement of the clutch.
When a shift stage of the hybrid electric vehicle is changed, the shift stage may be changed unexpectedly by incorrect operation of a shift lever or an unusual control signal of a TCU (transmission control unit) controlling the transmission.
Further, the vehicle may start at an unwanted speed caused by a problem of torque of the motor due to unusual input and output signals of the TCU and an HCU (hybrid control unit).
For example, there is a case in which the driver does not correctly operate the shift lever from an R range to an N range, and locates the shift lever to an intermediate position between the R range and the N range. At this time, an inhibitor switch connected to the shift lever generates an intermediate position signal and provides the intermediate position signal to the HCU.
However, the HCU misrecognizes a position of the shift lever as the R range, and generates a creep torque signal according to operation of the shift lever. The motor generates creep torque according to the creep torque signal, and thus the motor RPM is rapidly increased.
In another example, when the driver operates the shift lever from the N range to a D range, the HCU receives an input signal of the D range from the inhibitor switch, but a creep torque may be generated by the HCU in a state where the transmission is not changed to the D range. Thus the motor RPM is rapidly increased. At this time, if the transmission is changed to the D range after being delayed by a predetermined time from a time when the creep torque is generated, the vehicle starts at an unwanted speed.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.